(.NET Core C#) Send Email without Authentication (no Login)

Demonstrates how to send email using an SMTP server that does not require authentication.

An SMTP server that needs no authentication should be protected by a firewall, to prevent outsiders from using it as a SPAM server. To send email without logging in, simply set the mailman's SmtpAuthMethod property = "NONE".

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// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// The mailman object is used for sending and receiving email.
Chilkat.MailMan mailman = new Chilkat.MailMan();

// Set the SMTP server.  Perhaps it is the local machine.
mailman.SmtpHost = "localhost";
// Or perhaps it's a particular computer on the local network:
mailman.SmtpHost = "192.168.1.123";
// Or provide a local domain that resolves to an IP address on the local network:
mailman.SmtpHost = "mymailsesrver.com";

// Set the SmtpAuthMethod property = "NONE"
mailman.SmtpAuthMethod = "NONE";

// Set the SMTP login/password (this may be omitted given no authentication will take place)
// mailman.SmtpUsername = "myUsername";
// mailman.SmtpPassword = "myPassword";

// Create a new email object
Chilkat.Email email = new Chilkat.Email();

email.Subject = "This is a test";
email.Body = "This is a test";
email.From = "Chilkat Support <support@chilkatsoft.com>";
bool success = email.AddTo("Chilkat Admin","admin@chilkatsoft.com");
// To add more recipients, call AddTo, AddCC, or AddBcc once per recipient.

// Call SendEmail to connect to the SMTP server and send.
// The connection (i.e. session) to the SMTP server remains
// open so that subsequent SendEmail calls may use the
// same connection.  
success = mailman.SendEmail(email);
if (success != true) {
    Debug.WriteLine(mailman.LastErrorText);
    return;
}

// Some SMTP servers do not actually send the email until 
// the connection is closed.  In these cases, it is necessary to
// call CloseSmtpConnection for the mail to be  sent.  
// Most SMTP servers send the email immediately, and it is 
// not required to close the connection.  We'll close it here
// for the example:
success = mailman.CloseSmtpConnection();
if (success != true) {
    Debug.WriteLine("Connection to SMTP server not closed cleanly.");

}

Debug.WriteLine("Mail Sent!");